A rule proposed by EPA governing certain motor vehicle emission and fuel standards is a laudable effort to protect public health by continually improving air quality and reducing harmful vehicle emissions. The agency should also be applauded for recognizing that there are substantial clean air benefits that can result from full implementation of the federal Renewable Fuel Standard (RFS), not to mention specific and quantifiable positive health impacts.
The so-called “Tier 3 Motor Vehicle Emission and Fuel Standards” rule proposed by EPA has the potential to reduce pollutants from the on-road light-duty motor vehicle fleet for many years to come. However, in comments on the rule submitted to EPA this week by 25x’25, the Clean Fuels Development Coalition, the Urban Air Coalition and the Energy Future Coalition, the agency was cautioned that the proposed rule as written includes impediments to widespread commercialization of higher octane ethanol fuels which can provide critically needed public health, clean air and national security benefits.
EPA is specifically seeking input on whether to approve “an alternative certification fuel such as a high-octane 30 percent ethanol by volume (E30) blend” to enable more efficient engine design. Our response is that not only is it advisable to approve a mid-level ethanol blend certification fuel, but more importantly the agency must facilitate its use in order to comply with EPA’s obligation to regulate mobile source air toxics.
Many automakers have indicated their support for high octane fuels and recognize ethanol’s outstanding octane properties. Revising the rule to allow automakers a pathway to E30 certification is another key step in expanding ethanol markets. A requirement in the rule however that automakers must demonstrate the commercial availability of such fuel creates a “catch 22” dilemma. The fuel necessary for the next generation of motor vehicle engines cannot be introduced into the market until it is approved as a certification fuel, and it cannot be approved as a certification fuel until it is available in the market.
Corporate Average Fuel Efficiency (CAFE) credits now available to automakers in the production of flex-fuel vehicles were achieved completely independent of fuel supplies, and automakers responded to market developments and regulatory signals by making more FFVs available. This should certainly be the case with E30-capable or optimized vehicles, and if not corrected in this rule, would be a huge impediment to them.
It is important that EPA also recognize and quantify the public health benefits that can be achieved by reducing aromatic compounds in gasoline. Aromatic hydrocarbons are blended into gasoline to increase octane and upon combustion produce benzene, toluene, ethylbenzene, xylene, 1,3-butadiene, polycyclic aromatic hydrocarbons (PAHs), and a host of other toxic and carinogentic air pollutants which collectively cause serious health concerns.
To address this problem, EPA should use its authority under the Clean Air Act to require a phasedown in the aromatic content of all gasoline blends. That will open markets for cleaner and safer octane alternatives such as mid-level ethanol blends.
Unfortunately, as written the EPA proposed rule also significantly underestimates the carbon sequestration benefits of ethanol, with some recent studies showing that corn ethanol may be two to three times less carbon-intensive than gasoline than the 21-percent reduction level currently cited by the agency.
Ethanol’s carbon sequestration advantage over gasoline will only grow as higher levels of next-generation and cellulosic biofuels enter the market, in response to RFS requirements, while the increasing share of petroleum fuels from tar sands, oil shale and fracking technologies will result in substantially larger carbon footprints for the same amount of gasoline.
Renewable energy stakeholders stand ready to work with EPA and regulators in addressing these issues critical to public health, as well as to the economic benefits that would come from a Tier III rule that broadens its approach to the high octane fuels that could be made available to the American consumer.